Coronavirus outbreaks in meat plants continue to plague the nation’s meat industry, as another outbreak struck a Tyson Meats plant in Wilkesboro, North Carolina.

On Wednesday, Tyson announced that 570 of its 2,244 employees and contractors tested positive for COVID-19. The tests were taken from May 6 through 9.

Tyson said that the majority of those who tested positive did not show symptoms at the time of the test, and otherwise would not have been identified as COVID-19 positive.

The tests were part of an effort to improve safety procedures at meat plants nationwide. A number of meat plants closed last month due to localized outbreaks of the virus.

The outbreaks prompted President Donald Trump to issue an executive order to keep meat plants open amid the spread of the virus, provided resources for operators to protect employees while absolving the plants from liability for staying open.

The meat plant closures prompted a disruption in the meat supply, resulting in a number of grocery stores throughout the US to limit meat purchases.

“We are working closely with local health departments to protect our team members and their families, and to help manage the spread of the virus in our communities,” said Tom Brower, Senior Vice President of Health and Safety for Tyson Foods. “We are using the most up-to-date data and resources to support our team members, and we are committed to ensuring they feel safe and secure when they come to work.”